I can think of several formulas to use to determine a class champ that would be fair and equitable. I am very sure that the RC could come up with significantly more than I can (and perhaps some options would be acceptable to even the sarcastic members of the soaring community)...
Another benefit would allow someone to compete twice in the same class (toss the worst contest score?) and it would allow the guys with convertible ships (15/18M) to fly in both (traveling would be required) ;-)